Understanding Left Side Brain Injury

As you probably already know, there are two sides (or hemispheres) of the brain that each control different functions.

In general, the right side of the brain is responsible for non-verbal, intuitive actions like musical and artistic ability. The left side is in charge of verbal and logical functions.

Some specific functions of the left hemisphere include:

Logic and reasoning

Number skills

Analytic thought

Listening

Right-hand control

Sequential thinking

The left side is also considered the “language hub” of the brain. It is where the bulk of your language abilities lie, particularly your ability to produce and understand language.

That’s why most people with left brain injuries have difficulty comprehending and speaking words, a condition called aphasia.

We’ll take a closer look at aphasia, and the other effects of left hemisphere brain damage, next.

Effects of Left Side Brain Injury

Below are some of the major side effects of left side brain injury.

1. Aphasia

Aphasia is a language disorder that affects a person’s ability to produce and understand speech. It can also cause difficulties with reading and writing.

There are several types of aphasia that a person can develop after a left side brain injury. The three most common are:

Global aphasia. This is the most severe form of aphasia. A person with Global Aphasia cannot speak, read or write and can barely understand what is spoken to them.

Broca’s aphasia This one is also called “expressive” or “non-fluent” aphasia. With Broca’s aphasia, a person can understand what others say, but has difficulty speaking their own words. They can also read but cannot write.

Wernicke’s aphasia. This form is pretty much the exact opposite of Broca’s aphasia. In this form of aphasia, a person can speak fine, but cannot understand others.

The best way to treat aphasia in any form is to work with a speech-language pathologist who can create a custom plan that best fits your needs.

2. Apraxia of Speech

Not all language problems are caused by aphasia.

Sometimes after a left-side brain injury, your muscles used to form words are affected. This condition is called apraxia of speech.

With apraxia of speech, your brain has trouble coordinating the movements of all the different muscles in your mouth. This can make it difficult to form and pronounce words correctly.

Massed practice (i.e. high repetition) of oral-motor exercises is the best treatment for apraxia of speech.

Some oral-motor exercises you can do include blowing a whistle, yawning, and tongue strengthening exercises.

As you practice these exercises, you will help retrain your brain and eventually gain more control of your muscles.

For more exercises and tips on how to overcome apraxia of speech, we recommend seeing a speech language pathologist.

3. Dysarthria (slurred speech) and Dysphagia (difficulty swallowing)

Two other problems associated with left hemisphere brain damage are dysarthria and dysphagia.

Dysarthria refers to a weakness of the mouth and tongue that causes a person to slur their speech. Dysphagia is weakness of the muscles used for swallowing.

The two disorders often appear together because many of the muscles used for speaking are also needed for swallowing.

Once again, speech therapy exercises are the best ways to treat these problems.

If your swallowing is severely affected however, you should make sure you practice your exercises under the close supervision of a speech therapist to prevent any risk of choking.

4. Computation and Reasoning Problems

A left side brain injury can also cause issues with math and logic skills.

Brain games and cognitive training exercises are great ways to engage neuroplasticity and help you improve your logic and reasoning skills.

5. Right Side Weakness (hemiparesis)

Because the left side of the brain actually controls movement on the right side of the body, a common side effect of left hemisphere brain damage is right side weakness, also called hemiparesis.

In severe cases, a person can experience paralysis on their right side. (hemiplegia)

As with everything else related to brain injury recovery, the key to recovering movement on your right side is in activating your brain’s neuroplasticity through massed practice.

The more you practice an activity, the more the new neural pathways your brain forms in response to that activity are reinforced, and the easier the action becomes!

So to restore movement, you are going to need to practice lots of physical therapy exercises that utilize your affected muscles.

6. Right Side Neglect

After an injury to the left side of the brain, a person may experience something called right-side neglect.

This is where visual perception on the right side is affected, so that a person is completely unaware of that side. They do not even realize they are blind to everything on their right.

Right-side neglect is far less common then left-side neglect, but it can still occur.

Shared Effects of Left Side Brain Injury and Right Side Brain Injury

While there are some functions that are mainly controlled by either the left or right side of the brain, the brain itself works together as a whole. The right side of the brain contributes to left-side functions, and the left helps out the right, etc…

For example, although the left-side of the brain is known as the logical, problem-solving side, the right hemisphere helps us organize information and come up with creative solutions, making the right side just as necessary for problem solving as the left.

Alright, so why are we pointing all this out?

Well, the fact that the right and left hemispheres help each other means that sometimes the effects of left side brain injury and right side brain injury are not always as clear cut as this article may make it sound.

Some people with left hemisphere brain damage may have a few of the symptoms of right brain damage, and vice versa.

This article is meant to serve as a general guide to the most common effects of left side brain injury, but every person’s injury and path to recovery is unique.

All this is just to say that if your symptoms do not line up perfectly with this list, that is no reason to worry.

With that said, hopefully you now have a clearer picture of left side brain injury and the steps you need to take to start your recovery.